JPWO2007029506A1 - Ultrasonic sensor - Google Patents

Abstract

Provided is an ultrasonic sensor having a structure in which vibration of a piezoelectric element is hardly damped, a structure in which a terminal can be easily positioned at a predetermined position, and a structure in which the piezoelectric element and the terminal can be easily connected. . The ultrasonic sensor 10 includes a bottomed cylindrical case 12. A piezoelectric element 16 is formed on the bottom surface of the case 12, and a cushion member 20 is fitted on the side of the opening. The holding portion 26 of the cushion member 20 is fitted and held with the substrate 34 and the pin terminals 36a and 36b. On the substrate 34, electrodes 38a and 38b connected to the pin terminals 36a and 36b are formed. An opening 32 is formed on the upper surface of the cushion member 20. Lead wires 42a and 42b electrically connected to the piezoelectric element 16 are drawn from the opening 32 and connected to the electrodes 38a and 38b. The case 12 is filled with the elastic resin 44 from the opening 32.

Description

  The present invention relates to an ultrasonic sensor, and more particularly to a drip-proof ultrasonic sensor used for, for example, a back sonar of an automobile.

  FIG. 12 is an illustrative view showing one example of a conventional ultrasonic sensor. The ultrasonic sensor 1 shown in FIG. 12 includes a bottomed cylindrical case 2 made of aluminum or the like. One surface of the piezoelectric element 3 is bonded to the bottom surface inside the case 2. A foamable resin 4 such as foamable silicon is filled in almost the entire interior of the case 2 so as to cover the piezoelectric element 3. Further, a substrate 6 having two terminals 5 a and 5 b is attached to the opening of the case 2 so as to cover the foamable resin 4. Electrodes 7a and 7b connected to the terminals 5a and 5b are formed on both surfaces of the substrate 6, respectively. One terminal 5 a is connected to the other surface of the piezoelectric element 3 by an electrode 7 a and a wire 8 formed inside the substrate 6. The other terminal 5 b is connected to one surface of the piezoelectric element 3 via the case 2 by an electrode 7 b and solder 9 formed outside the substrate 6.

  When the distance to the object to be detected is measured using the ultrasonic sensor 1 shown in FIG. 12, the piezoelectric element 3 is excited by applying a drive voltage to the terminals 5a and 5b. Due to the vibration of the piezoelectric element 3, the bottom surface of the case 2 also vibrates, and an ultrasonic wave is emitted in a direction orthogonal to the bottom surface as shown by an arrow in FIG. When the ultrasonic wave emitted from the ultrasonic sensor 1 is reflected by the object to be detected and reaches the ultrasonic sensor 1, the piezoelectric element 3 vibrates and is converted into an electric signal, and the electric signal is output from the terminals 5a and 5b. . Therefore, the distance from the ultrasonic sensor 1 to the object to be detected can be measured by measuring the time from when the drive voltage is applied until the electrical signal is output.

  In the ultrasonic sensor 1 shown in FIG. 12, vibration of the entire case 2 can be suppressed by filling the inside of the case 2 with the foamable resin 4. In addition, ultrasonic waves generated inside the case 2 are scattered and absorbed by a large number of foam holes present in the foamable resin 4. Thereby, both vibration of case 2 itself and the ultrasonic wave which stays inside case 2 can be suppressed efficiently, and reverberation characteristics can be improved (refer to patent documents 1).

  FIG. 13 is an illustrative view showing another example of a conventional ultrasonic sensor. Compared to the ultrasonic sensor 1 shown in FIG. 12, the ultrasonic sensor 1 shown in FIG. 13 is not particularly directly attached to the case 2 but the substrate 6 having the terminals 5 a and 5 b is filled in the case 2. It is covered with an elastic body 4a made of silicon rubber or the like. Furthermore, a sealing material 4b made of a silicon material having a high gas barrier property is provided on the exposed surface of the elastic body 4a. One terminal 5a is connected to the piezoelectric element 3 via the lead wire 8a, and the other terminal 5b is connected to the piezoelectric element 3 via the lead wire 8b and the case 2, respectively.

  In the ultrasonic sensor 1 shown in FIG. 13, since the sealing material 4b made of a silicon material having a high gas barrier property is provided on the exposed surface of the elastic body 4a, it is effective for the corrosive gas to enter the case 2. Furthermore, since a silicon material is used as the sealing material 4b, the reverberation characteristics can be maintained at a sufficient level even when used in a low temperature environment where the temperature changes drastically ( Patent Document 2).

JP-A-11-266498 JP 2001-197592 A

  In the conventional ultrasonic sensor 1 shown in FIG. 12, since the substrate 6 having the terminals 5a and 5b is fixed in direct contact with the side surface of the case 2, the vibration of the piezoelectric element 3 is transmitted through the case 2 and the substrate 6 and the terminals. It will be damped from 5a and 5b.

On the other hand, in the ultrasonic sensor 1 shown in FIG. 13, since the substrate 6 having the terminals 5a and 5b is covered with the elastic body 4a made of silicon rubber or the like filled in the case 2, vibration through the case 2 or the like. The structure is less susceptible to damping.
However, in the ultrasonic sensor 1 shown in FIG. 13, the positions of the substrate 6 and the terminals 5a and 5b associated therewith are often shifted by the filling work of silicon rubber or the like to become the elastic body 4a, and the positions of the terminals 5a and 5b are exceeded. It is difficult to set a predetermined position in the sonic sensor, and there is a possibility that a problem may occur during mounting.

  Further, in each ultrasonic sensor 1 shown in FIGS. 12 and 13, the wires 8 and lead wires 8a and 8b inside the case 2 and the terminals 5a and 5b are joined by soldering, welding, or the like. In order to assemble the substrate 6 and the case 2, the wires 8 and the lead wires 8a and 8b need to be formed long, and excessive stress is applied to the joint portion of the wire 8 and the lead wires 8a and 8b when the case 2 is assembled. The wiring process to the terminals 5a and 5b has a high difficulty level.

  Therefore, a main object of the present invention is a structure in which the vibration of the piezoelectric element is not easily damped, a structure in which the terminal is easily positioned at a predetermined position, and the piezoelectric element and the terminal can be easily connected. It is to provide an ultrasonic sensor that is a structure.

An ultrasonic sensor according to the present invention is fitted to a bottomed cylindrical case, a piezoelectric element formed on a bottom surface inside the case, a cushion member fitted to an opening side portion of the case, and a cushion member. The substrate is held by the cushion member and the terminal is fixed, the electrode formed on the substrate and electrically connected to the terminal, the upper surface of the cushion member, and the electrode inside the case and the electrode on the substrate. It is an ultrasonic sensor provided with the opening part which leads.
The ultrasonic sensor according to the present invention includes, for example, a connecting member such as a lead wire and a lead ribbon that is electrically connected to a piezoelectric element, drawn from an opening, and electrically connected to an electrode on a substrate, and the opening. And a filler such as a foamable resin filled in the case.
In the ultrasonic sensor according to the present invention, for example, the fitting structure between the cushion member and the substrate on which the terminal is fixed is a cantilever structure, and an opening is formed around the cantilever structure. Is preferred.
Furthermore, in the ultrasonic sensor according to the present invention, for example, a through hole corresponding to the terminal is formed in the cushion member, and the substrate on which the terminal is fixed is held by the cushion member by inserting the terminal into the through hole. It is preferable.

In the ultrasonic sensor according to the present invention, the piezoelectric element is formed in the case, and the substrate on which the terminal is fixed is held by the cushion member fitted into the case, so the substrate does not directly contact the case, The vibration of the piezoelectric element is buffered by the cushion member, and is not easily transmitted to the terminal and is not easily damped.
Moreover, in the ultrasonic sensor according to the present invention, since the substrate on which the terminal is fixed is held by the cushion member fitted to the case, the terminal can be easily positioned at a predetermined position.
Furthermore, in the ultrasonic sensor according to the present invention, the opening that leads to the inside of the case and the electrode on the substrate is formed on the upper surface of the cushion member. For example, a lead wire or a lead ribbon that is electrically connected to the piezoelectric element. This connection member can be pulled out from the opening and easily connected to the electrode on the substrate, so that the piezoelectric element and the terminal can be easily connected.
In the ultrasonic sensor according to the present invention, if a filler having elasticity such as foamable resin is filled into the case from the opening, vibration of the entire case can be suppressed.
In the ultrasonic sensor according to the present invention, for example, when the fitting structure between the cushion member and the substrate on which the terminal is fixed is a cantilever structure and an opening is formed around the cantilever structure, a large opening is obtained. The portion can be formed, and the connection work between the piezoelectric element and the terminal and the filling work of the filler are further facilitated.
Furthermore, in the ultrasonic sensor according to the present invention, for example, by forming a through hole corresponding to the terminal in the cushion member and inserting the terminal into the through hole, the substrate to which the terminal is fixed is held by the cushion member. The terminal is directly held by the cushion member, which makes it easier to position the terminal at a predetermined position.

  According to the present invention, the vibration of the piezoelectric element is less likely to be damped, the terminal is easily positioned at a predetermined position, and the piezoelectric element and the terminal can be easily connected. An ultrasonic sensor is obtained.

  The above-described object, other objects, features, and advantages of the present invention will become more apparent from the following description of the best mode for carrying out the invention with reference to the drawings.

It is a top view solution figure which shows an example of the ultrasonic sensor concerning this invention. It is a front view solution figure of the ultrasonic sensor shown in FIG. It is a side view solution figure of the ultrasonic sensor shown in FIG. It is a disassembled perspective view of the ultrasonic sensor shown in FIG. It is an illustration figure which shows the board | substrate etc. with which the pin terminal used for the ultrasonic sensor shown in FIG. 1 was press-fitted. It is an illustration figure which shows the cushion member used for the ultrasonic sensor shown in FIG. FIG. 7 is an illustrative view showing a state where the pin terminal shown in FIG. 5 is fitted in the cushion member shown in FIG. 6. It is an illustration figure which shows the case, piezoelectric element, etc. which are used for the ultrasonic sensor shown in FIG. It is a top view solution figure which shows the other example of the ultrasonic sensor concerning this invention. It is a top view solution figure which shows the further another example of the ultrasonic sensor concerning this invention. It is a front view solution figure which shows the other example of the ultrasonic sensor concerning this invention. It is an illustration figure which shows an example of the conventional ultrasonic sensor. It is an illustration figure which shows the other example of the conventional ultrasonic sensor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Ultrasonic sensor 12 Case 12a Bottom face part 12b Side wall 14 Cavity part 16 Piezoelectric element 18 Sound absorbing material 20 Cushion member 22 Attachment part 24 Step part 26, 26a, 26b Holding part 28a, 28b Recessed part 30a, 30b Through-hole 32 Opening part 34, 34a, 34b Substrate 36a, 36b Pin terminal 38a, 38b Electrode 40 Sound absorbing material 42a, 42b Lead wire 43a, 43b Lead ribbon 44 Elastic resin

  1 is a plan view illustrating an example of an ultrasonic sensor according to the present invention, FIG. 2 is a front view illustrating the ultrasonic sensor, and FIG. 3 is a side view illustrating the ultrasonic sensor. FIG. 3 is an exploded perspective view of the ultrasonic sensor. Note that FIG. 1 and FIG. 4 do not show the foamable resin filled in the case and lead wires for electrical connection.

  An ultrasonic sensor 10 shown in FIG. 1 includes a bottomed cylindrical case 12, for example. This case 12 is comprised by the bottom face part 12a and the side wall 12b. Case 12 is formed of a metal material such as aluminum, for example. As shown in FIGS. 1 and 4, the cavity 14 inside the case 12 is formed to have, for example, a substantially elliptical cross-sectional shape. Therefore, the case 12 is formed with a thin wall thickness at one facing portion of the side wall 12b and a thick wall thickness at the facing portion in the direction orthogonal to the side wall 12b. Note that the shape of the cavity 14 is designed according to desired characteristics because the way in which the ultrasonic wave emitted from the ultrasonic sensor 10 spreads is determined by the shape of the cavity 14.

  Inside the case 12, a piezoelectric element 16 is attached to the inner surface of the bottom surface portion 12a. The piezoelectric element 16 is formed by forming electrodes on both sides of a disk-shaped piezoelectric substrate, for example. Then, the electrode on one surface side of the piezoelectric element 16 is bonded to the bottom surface portion 12a with a conductive adhesive or the like. Furthermore, a sound absorbing material 18 made of felt, for example, is bonded onto the electrode on the other surface side of the piezoelectric element 16 by an adhesive. The sound absorbing material 18 is used to absorb ultrasonic waves from the piezoelectric element 16 toward the inside of the case 12 and functions to prevent the vibration of the piezoelectric element 16 from being hindered by an elastic resin 44 described later.

  A cushion member 20 made of, for example, silicon rubber is fitted into the opening side portion of the case 12. The cushion member 20 has an action of suppressing the propagation of unnecessary vibrations from the case 12 to the outside and the invasion of unnecessary vibrations from the outside to the case 12, and is used as a cushioning material. The cushion member 20 includes a cylindrical attachment portion 22. The attachment portion 22 is attached to the case 12, has a stepped portion 24 at the center in the inner height direction, and has an inner diameter of the upper half portion in the height direction narrower than the outer diameter of the case 12. The inner diameter of the lower half portion in the vertical direction is formed to be approximately the same as the outer diameter of the case 12. Therefore, the attachment portion 22 can be attached to the case 12 by fitting the lower half portion thereof to the opening side portion of the case 12.

  In the attachment portion 22, for example, a rectangular parallelepiped holding portion 26 is formed integrally with the attachment portion 22 so as to extend from the upper part to the center. The holding portion 26 is for holding a substrate 34 and pin terminals 36a and 36b, which will be described later. In the lower part of the holding part 26, a recess 28a into which a part of a substrate 34 described later is fitted and a recess 28b into which a part of a sound absorbing material 40 described later is fitted are formed in a step shape. In this case, the recess 28a is formed on the distal end side of the holding portion 26, and the recess 28b is formed below the recess 28a and extending toward the attachment portion 22 than the recess 28a. Further, at approximately the center of the cushion member 20, two through holes 30 a and 30 b extending in the vertical direction are formed in the holding portion 26 at intervals in the width direction of the holding portion 26. These through holes 30a and 30b are for inserting pin terminals 36a and 36b described later, and are formed corresponding to the pin terminals 36a and 36b.

  Further, on the upper surface of the cushion member 20, a substantially C-shaped opening 32 is provided inside the attachment portion 22 and outside the holding portion 26, that is, around a cantilever structure described later such as the holding portion 26. Is formed. The opening 32 is used when electrically connecting lead wires 42a and 42b to electrodes 38a and 38b, which will be described later, and when filling the inside of the case 12 with the elastic resin 44. It is formed so as to communicate with electrodes 38a and 38b on the substrate 34 described later.

The board 34 and the pin terminals 36 a and 36 b are fitted and held in the holding portion 26 of the cushion member 20. As the substrate 34, for example, a rectangular glass epoxy substrate is used, and two pin terminals 36a and 36b are press-fitted at a distance in the width direction and fixed to the substrate 34. In addition, two electrodes 38a and 38b are formed on the upper surface of the substrate 34 at intervals in the width direction, and these electrodes 38a and 38b are electrically connected to the pin terminals 36a and 36b, respectively.
Then, the pin terminals 36 a and 36 b are inserted into the through holes 30 a and 30 b of the holding part 26 from below, respectively, and a part of the substrate 34 is fitted into the concave part 28 a of the holding part 26. Thereby, the substrate 34 and the pin terminals 36 a and 36 b are held by the holding portion 26 of the cushion member 20. In this case, the fitting structure of the holding portion 26 of the cushion member 20, the substrate 34, and the pin terminals 36 a and 36 b is a cantilever structure, and the pin terminals 36 a and 36 b are located substantially at the center of the cushion member 20.

  In addition, a rectangular plate-like sound absorbing material 40 made of, for example, felt is adhered to the lower surface of the substrate 34 with an adhesive, and a part of the sound absorbing material 40 is fitted into the recess 28 b of the holding portion 26. The sound absorbing material 40 is used to absorb ultrasonic waves from the substrate 34 toward the inside of the case 12.

One end of one lead wire 42a made of, for example, polyurethane copper wire is connected to the inner surface of the side wall 12b of the case 12 as a connecting member. Therefore, the lead wire 42 a is electrically connected to the electrode on one surface side of the piezoelectric element 16 through the case 12. The other end of the lead wire 42 a is drawn out from the opening 32 and connected to one electrode 38 a on the substrate 34. Therefore, the electrode on one surface side of the piezoelectric element 16 is electrically connected to the one pin terminal 36a via the case 12, the lead wire 42a, and the electrode 38a.
In addition, one end of the other lead wire 42 b made of, for example, a polyurethane copper wire as a connecting member is connected to the electrode on the other surface side of the piezoelectric element 16. The other end of the lead wire 42 b is drawn from the opening 32 and connected to the other electrode 38 b on the substrate 34. Therefore, the electrode on the other surface side of the piezoelectric element 16 is electrically connected to the other pin terminal 36b via the lead wire 42b and the electrode 38b.

  The inside of the case 12 and the opening 32 of the cushion member 20 are filled with an elastic resin 44 such as foamable silicon as a filler from the opening 32.

  Next, an example of a method for manufacturing the ultrasonic sensor 10 will be described.

  First, as shown in FIG. 5, a substrate made of a glass epoxy substrate in which electrodes 38a and 38b are printed on the upper surface and pin terminals 36a and 36b are press-fitted into the through holes and electrically connected to the electrodes 38a and 38b, respectively. 34 is prepared. A sound absorbing material 40 made of felt is bonded to the lower surface of the substrate 34 with an adhesive.

  Further, as shown in FIG. 6, a cushion member 20 made of silicon rubber having a mounting portion 22 and a holding portion 26 is formed.

  Then, as shown in FIG. 7, pin terminals 36 a and 36 b are inserted into the through holes 30 a and 30 b formed in the holding portion 26 of the cushion member 20, respectively, and are further inserted into the recesses 28 a and 28 b formed in the holding portion 26. By fitting a part of the board 34 and a part of the sound absorbing material 40, the board 34 and the pin terminals 36 a and 36 b are fitted into the holding part 26 of the cushion member 20 and held by the holding part 26.

  Further, as shown in FIG. 8, a case 12 is prepared, and an electrode on one surface side of the piezoelectric element 16 is bonded to the inner surface of the bottom surface portion 12a of the case 12 with a conductive adhesive. Furthermore, one end of one lead wire 42 a made of polyurethane copper wire is soldered to the inner surface of the side wall 12 b of the case 12, and one end of the other lead wire 42 b made of polyurethane copper wire is used as an electrode on the other surface side of the piezoelectric element 16. Soldered. Further, in the case 12, a sound absorbing material 18 made of felt is adhered to the electrode on the other surface side of the piezoelectric element 16 with an adhesive.

  2 and 3, the attachment portion 22 of the cushion member 20 is fitted to the opening side portion of the case 12, and the other end of one lead wire 42a is drawn out from the opening portion 32, and one electrode 38a. Furthermore, the other end of the other lead wire 42b is drawn out from the opening 32 and soldered to the other electrode 38b.

  Then, the inside of the case 12 and the opening 32 of the cushion member 20 are filled with an elastic resin 44 such as foamable silicon as a filler. In this case, the resin before foaming is injected into the inside of the case 12 from the opening 32 of the cushion member 20, and the elastic resin 44 is filled by heating and curing the resin. Thereby, the ultrasonic sensor 10 is manufactured.

  When this ultrasonic sensor 10 is used, for example, as an automobile back sonar, the piezoelectric element 16 is excited by applying a driving voltage to the pin terminals 36a and 36b. At this time, even if the periphery of the piezoelectric element 16 is covered with the elastic resin 44, the vibration region of the piezoelectric element 16 is secured by the sound absorbing material 18 bonded to the piezoelectric element 16. Due to the vibration of the piezoelectric element 16, the bottom surface portion 12a of the case 12 also vibrates, and an ultrasonic wave is emitted in a direction orthogonal to the bottom surface portion 12a. When the ultrasonic wave emitted from the ultrasonic sensor 10 is reflected by the object to be detected and reaches the ultrasonic sensor 10, the piezoelectric element 16 vibrates and is converted into an electric signal, and the electric signal is output from the pin terminals 36a and 36b. Is done. Therefore, the distance from the ultrasonic sensor 10 to the object to be detected can be measured by measuring the time from when the drive voltage is applied until the electrical signal is output.

  In the ultrasonic sensor 10, since the case 12 is filled with the elastic resin 44, vibration of the entire case 12 can be suppressed.

  In the ultrasonic sensor 10, vibration interference between the case 12 and the pin terminals 36a and 36b, such as propagation of vibration from the case 12 to the pin terminals 36a and 36b, causes the sound absorbing material 18, the cushion member 20, the sound absorbing material 40, and the elasticity. Since it is reduced or blocked by the resin 44, the influence of the vibration leakage signal on the reverberation signal and the received signal at the time of object detection is suppressed, that is, the reverberation characteristics are not deteriorated due to vibration leakage and the pin terminal 36a from the outside. And the influence of propagation of unnecessary vibrations etc. via 36b is also suppressed.

  Further, in this ultrasonic sensor 10, since the pin terminals 36a and 36b are inserted and fitted into the through holes 30a and 30b formed in the cushion member 20 fitted to the case 12, the pin terminals 30a and 30b with respect to the case 12 are inserted. It is possible to improve the positioning system. That is, the base portions of the pin terminals 36a and 36b coincide with the through holes 30a and 30b formed in the cushion member 20, and the central portion of the case 12 and the central portion of the cushion member 20 coincide with each other. High positional accuracy is obtained as the positional accuracy of the pin terminals 36a and 36b.

  Further, in the ultrasonic sensor 10, the case 12, the cushion member 20, the substrate 34, and the pin terminals 36a and 36b can be easily assembled with high positional accuracy by fitting without requiring an adhesive or a special positioning jig. Is possible.

  Further, in this ultrasonic sensor 10, after the cushion member 20 is fitted to the case 12, the lead wires 42 a and 42 b can be soldered from the opening 32 of the cushion member 20 to the electrodes 38 a and 38 b of the substrate 34. Further, the connection work between the piezoelectric element 16 and the pin terminals 36a and 36b is facilitated, and the number of work steps can be reduced.

  In the ultrasonic sensor 10, only the pin terminals 36a and 36b protrude from the upper surface of the cushion member 20, that is, the area of the holding portion 26 of the cushion member 20 that holds the pin terminals 36a and 36b and the like is relatively small. Therefore, the area of the opening 32 for filling the material of the elastic resin 44 such as foamable silicon can be made relatively large, and the filling operation of the material becomes easy. Generation is suppressed, and quality such as residual characteristics is stabilized.

  Further, in this ultrasonic sensor 10, since the elastic resin 44 is also filled on the substrate 34 and around the holding portion 26 holding the substrate 34 and the pin terminals 36a and 36b, the holding portion 26, the substrate 34, the pin terminal 36 a and 36 b are reinforced with the elastic resin 44.

  FIG. 9 is an illustrative plan view showing another example of the ultrasonic sensor according to the present invention. In the ultrasonic sensor 10 shown in FIG. 9, the holding part 26 of the cushion member 20 is formed shorter than the ultrasonic sensor 10 shown in FIG. Therefore, the pin terminals 36a and 36b are disposed between the central portion of the cushion member 20 and the attachment portion 22, and the opening 32 of the cushion member 20 is formed wider.

  FIG. 10 is an illustrative plan view showing still another example of the ultrasonic sensor according to the present invention. In the ultrasonic sensor 10 illustrated in FIG. 10, the cushion member 20 includes two holding portions 26 a and 26 b that are divided instead of one holding portion 26 as compared to the ultrasonic sensor 10 illustrated in FIG. 9. The substrate 34 is divided into two substrates 34a and 34b, and the opening 32 of the cushion member 20 is widely formed in a substantially T-shape.

The ultrasonic sensor 10 shown in FIG. 9 and the ultrasonic sensor 10 shown in FIG. 10 have the same effects as the ultrasonic sensor 10 shown in FIG.
Further, in the ultrasonic sensor 10 shown in FIG. 9 and the ultrasonic sensor 10 shown in FIG. 10, the size of the opening 32 of the cushion member 20 is larger than that of the ultrasonic sensor 10 shown in FIG. The electrical connection to the electrodes 38a and 38b and the filling of the material of the elastic resin 44 are further facilitated.

FIG. 11 is an elevational view showing still another example of the ultrasonic sensor according to the present invention. In the ultrasonic sensor 10 shown in FIG. 11, compared to the ultrasonic sensor 10 shown in FIG. 1, a metal plate is formed by pressing instead of the linear lead wires 42 a and 42 b made of polyurethane copper wire as a connecting member. Band-shaped lead ribbons 43a and 43b are used.
The ultrasonic sensor 10 shown in FIG. 11 has the same effect as each of the ultrasonic sensors 10 described above.
Further, in each of the conventional ultrasonic sensors 1 shown in FIGS. 12 and 13, the wire 8 and the lead wires 8 a and 8 b are used because of the structure, and it is difficult to use a belt-like lead ribbon. In the ultrasonic sensor 10 shown in FIG. 11, since the wiring is provided from the opening 32 of the cushion member 20 to the electrodes 38a and 38b on the substrate 34, the strip-shaped lead ribbons 43a and 43b can be used. Wiring is possible, and options such as wiring automation increase.

  In addition, although each part is prescribed | regulated by specific magnitude | size, shape, arrangement | positioning, material, and number in each above-mentioned ultrasonic sensor, in this invention, they may be changed arbitrarily.

  The ultrasonic sensor according to the present invention is used, for example, in a back sonar of an automobile.

Claims (4)

Bottomed cylindrical case,
A piezoelectric element formed on the bottom surface inside the case,
A cushion member fitted to the opening side of the case;
A substrate that is fitted to the cushion member and held by the cushion member, and a terminal is fixed;
An ultrasonic sensor formed on the substrate and electrically connected to the terminal, and an opening formed on an upper surface of the cushion member and leading to the inside of the case and the electrode on the substrate . A connecting member electrically connected to the piezoelectric element, drawn out from the opening, and electrically connected to the electrode on the substrate; and a filler filled into the case from the opening The ultrasonic sensor according to claim 1. The fitting structure between the cushion member and the substrate on which the terminal is fixed is a cantilever structure,
The ultrasonic sensor according to claim 1, wherein the opening is formed around the cantilever structure.   The through-hole corresponding to the said terminal is formed in the said cushion member, The said board | substrate with which the said terminal is being fixed is hold | maintained by the said cushion member by inserting the said terminal in the said through-hole. Item 4. The ultrasonic sensor according to any one of Items 3 to 3.

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